ENTRANCE STAIRS FOR TRANSPORTATION VEHICLE, FOR INSTANCE FOR AIRCRAFT PLANE Russian patent published in 2008 - IPC B64C1/24 

FIELD: transportation.

SUBSTANCE: entrance stairs contain door frame with hinge brackets mounted in lower inner part of door frame with possibility to be flipped down, locking closure device and door mass balance. Entrance stairs are equipped with stairs transformation mechanism containing shafts positioned in parallel to hinge axis, at that, a stair is fixed on shaft central part and gripping devices are located at its ends. Gripping devices contact with catchers of locking closure device which are rigidly fixed in the door opening. The mentioned shafts are kinematically linked with each other by synchronising mechanism, at that, one of the stairs is made rotating on shaft and the other - builtup of two perts. Synchronising mechanism includes flat strut pivotally connected with door frame, and door mass balancer includes above-mentioned hinge bracket where groove is performed for weight synchroniser. Door mass balancer includes buckle performed with variable radius to compensate door weight throughout entire span of its opening.

EFFECT: operating safety improvement.

3 cl, 5 dwg